Barefoot in Paris: Ina's Provencal Vegetable Soup Au Pistou

Spring is in the air and that means that lighter dishes are on their way back to my kitchen. Not too light of course, but I tend to do away with the heavy stews and super-rich pastas that are the staple my winter cooking. This soup is the perfect transition dish because it feels hearty and light at the same time. It also has a spring freshness thanks to the pistou, a pesto-like sauce that infuses the soup with fresh basil, tomato and garlic. Unlike the Italian pesto, however, there are no pine nuts. This recipe also adapts the traditional version, as it contains leeks. I think they really work here. 
I made this for lunch today and I was unable to limit myself to just one bowl. Oh yes, I went in for doubles. It's that kind of wonderful. 

In addition to the great flavor, I have most of the ingredients in my pantry or fridge: onions, olive oil, leeks, potatoes, carrots, salt, pepper, broth, spaghetti and parmesan. And I happen to have saffron threads on hand thanks to my husband's aunt who just returned from a trip to the Middle-East and came back with spice gifts for me.
Hope you enjoy the soup as much as I did... 

Provencal Vegetable Soup Au Pistou (Courtesy of Ina Garten, Barefoot in Paris) 
Yields 6 to 8

Ingredients

• 2 tablespoons good olive oil
• 2 cups chopped onions (2 onions)
• 2 cups chopped leeks, white and light green parts (2 to 4 leeks)
• 3 cups 1/2-inch-diced unpeeled boiling potatoes(1 pound)
• 3 cups 1/2-inch-diced carrots (1 pound)
• 1 1/2 tablespoons kosher salt
• 1 teaspoon freshly ground black pepper
• 3 quarts homemade chicken stock or canned broth (I use vegetable stock)I sometimes substitute part of the broth with water. 
• 1 teaspoon saffron threads
• 1/2 pound haricots verts, ends removed and cut in 1/2 (I went in 1/3 for smaller pieces)
• 4 ounces spaghetti, broken in pieces
• 1 cup Pistou, recipe follows
• Freshly grated Parmesan, for serving

Directions

Heat the olive oil in a large stockpot, add the onions, and saute over low heat for 10 minutes, or until the onions are translucent. Add the leeks, potatoes, carrots, salt, and pepper and saute over medium heat for another 5 minutes. Add the chicken stock and saffron, bring to a boil, then simmer uncovered for 30 minutes, or until all the vegetables are tender. Add the haricots verts and spaghetti, bring to a simmer, and cook for 15 more minutes.

To serve, whisk 1/4 cup of the pistou into the hot soup, then season to taste. Depending on the saltiness of your chicken stock, you may need to add up to another tablespoon of salt. Serve with grated Parmesan cheese and more pistou.

Pistou:

4 large garlic cloves
1/4 cup tomato paste
24 large basil leaves
1/2 cup freshly grated Parmesan
1/2 cup good olive oil

Place the garlic, tomato paste, basil, and Parmesan in the bowl of a food processor and puree. With the motor running, slowly pour the olive oil down the feed tube to make a paste. Pack into a container, pour a film of olive oil on top, and close the lid.

Yield: 1 cup